Means for regulating the temperature of heating systems.



No. 710,30]. Patented Sept. 30, I902.

W. P. POWERS. MEANS FOR REGULATING THE'TEMPEBAT URE 0F HEATING SYSTEMS.

(Application filed Dec. 26, 1896.)

2 Sheets-Sheet I.

(No Model.)

THrI uonn s PEYERS cu. moruuwu. WASHINGTON, u. c

- 'No. 7|0,30.l. Patented Sept. 30, I902.

W. P. PUWERS.

MEANS FOR BEGULATING THE TEMPERATURE OF HEATING SYSTEMS.

I (Application filed Dec. 26, 1896.) (No Model.) 2 Sheets-Sheet 2.

UNITED STATES \VILLIAM P. POTVERS, OF CHICAGO, ILLINOIS.

MEANS FOR REGULATING THE TEMPERATURE OF HEATING SYSTEMS.

SPECIFICATION forming part of Letters Patent- No. 710,301, datedSeptember 30, 1902.

Application filed December 26. 1896. Serial No. 617,121. (No model.)

To all whom it may concern:

Be it known that I, WILLIAM P. POWERS, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented certain new and useful Improvements in Means for Regulating theTemperature in Heating Systems, of which the following is aspecification. This invention relates to the automatic control oftemperature in systems where the heating is effected by currents of hotand cold air,

either by natural circulation or by the help of mechanical appliances,the intention being to secure such control bythe use of compressed airthermostatically maintained at a pressure proportionate to thetemperature and suitable pressure-motors in which this variable pressure isutilized to produce the necessary movements of the dampers controllingthe supply of hot and cold air. An appliance of this kind is shown inLetters Patent issued to me April 21, 1896, No. 558,610, and also inLetters Patent issued to me February 11, 1896, No. 554,398. In both ofthese patents the thermostatic action comes primarily from the expansionof a volatile liquid con fined in an elastic chamber, the movable sideof which produces the mechanical effects nec-' essary to bring into playthe heat-controlling influences.

In the present invention I use, preferably, the well-known form ofthermostat, composed of two substances having dissimilar rates ofexpansion, by which a movementin one direction or the other is producedat the free end of the thermostat by changes of temperature. Inconnection with this thermostatic bar I use a pressure-chamber having aconstant but restricted supply of compressed air, the operation beingsubstantially like that described in Patent No. 236,520, of January 11,1881, issued to George lVestinghouse, Jr., in which a thermostat isarranged to open and close by its movement an escape, by means of whichthe air-pressure passing into the pressure-chamber is made effective oruon'effective, as the case may be. In my device whenever pressureaccumulates in this chamber, owing to the closing partially or wholly ofthe escape-opening, it results in a movement of the diaphragm of thepressure-chamber and through suitable connections serves to open a valvecontrolling a supply of fluid-pressure, which is thus permitted to flowinto another and larger pressure-chamber, by means of which theheat-controlling devices are operated This air-pressure also acts inopposition to the movement of the diaphragm which is under the influenceof theinitial pressure, and thereby serves to limit its action andpermit the opening of the valve to an amount just sufficient to producea pressure in the main pressure-motor equal to that existing in thechamber which is thermostatically controlled and which I willhereinafter call the primary one. The pressure-chamber operating theheat-controlling devices I will call the secondary one.

Figure l is a view, partly in section, of the thermostat and primarymotor. Fig. 2 is a similar view showing a modified form of primarymotor. Fig. 3 is a similar view of the thermostat in connection withstill another form of primary motor. Fig. 4 shows the secondary pressurechamber or motor as ordinarily constructed; and Fig. 5 is a diagrammaticview of the complete system, showing the manner of its operation. Fig. 6is a view of another modified form of primary motor. In Fig. 1, Arepresents the well-known ther mostatic bar, formed of materials havingdifferent rates of expansion-for instance, vulcanized rubber and steel.This is hinged at the upper end to the frame of the thermostat, and itsposition is made adjustable by the screw 1 At its lower and free end isarranged a pad Z), of some soft substance, usually patent-leather, whichoperates in juxtaposition to the small orifice C, communicating with thepressure-chamber D. primary pressurechamber there is a constant supplyof compressed air or other gas, the amount of which is restricted by theadjusting-valve E. A very limited amount of fluid is sufficient toanswer the purpose. It is common to use air-pressure maintained in asuitable tank by some form of air-compressor, ordinarily either steam orhydraulic. The escape-opening C must be larger than the passage throughwhich the air-pressure enters, so that when open the air will escapefrom the primary chamber faster than it can enter through therestricting-valve E. This primary pressure-chamber is provided with anInto this I elastic diaphragm F, to which is attached a piston-plate G,which when the diaphragm is flexed by pressure impinges against the stemof the valve H and serves to open same against the air-pressure-and theforce of the spring I, which constantly tends to close the valve. Thepassage controlled by valve I-I ordinarily connects with the passageleading to the primary pressure-chamber behind the restricting-valve E,so that one source of airpressure answers for both. This, however, isnot essential, as these two pressures might be taken from differentsources. Connecting with the valve side of the primary pressurechamberthere is an opening J, which connects by means of a pipe with the motorwhich operates the dampers or heat-controlling devices. At K a pipe isconnected which leads to the tank containing the supply offluid-pressure. At t is a small escape-valve controlling the dischargeof fluid-pressure from the valve side of the primary chamber and themotor connected therewith.- This valve is adjusted in amanner to permitthe air to escape very slowly, and there is accordingly a constantdischarge whenever pressure exists in the motor and its connections.

The operation is as follows: Supposing that the escape-opening C is openand the temperaturein the apartment in which the thermostat is locatedis rising, under the influence of the increasing temperature, thethermostatic bar A expanding more rapidly on the out than the in side, amovement is produced at the free end which results in limiting theescape of air at C. This results in apressure accumulating in thechamber D in direct proportion to the relation between the amount of airpassing through valve E and that escaping at 0, this pressure increasingas valve 0 is more completely closed. When sufficient pressure isdeveloped in chamber D to overcome the tension of spring I and theresisting air-pressure, the result is the unseating of the valve H,which permits a movement of the air into the pressure-chamber andthrough the connecting-passage into the damper-operating motor. Wheneverthis pressure equals that developed in the primary pressure-chamber, thediaphragm moves back and valve H returns to its seat from the effects ofspring I, thus shutting off the passage of any further supply of airinto the operating-motor. As the air in the motor and connecting-pipesand chamber is depleted through the constant escape at i, the pressurebecoming less than that in the primary pressure-chamber, a slightmovement of the diaphragm will occur, which will open the valve H andadmit a further supply of air to maintain the necessary equilibrinm. Ifnow through the temperature still further rising the thermostatic barshall cause the pad at its lower end to come closer to and therebyfurther restrict the escapeopening C, it will result in an increase ofpressure in the chamber D, which, through the process already described,will result in the admission of a greater pressure on the opposite sideof thediaphragm and in the mofor connecting therewith. It is thus seenthat the pressure in the motor will at all times be substantially thesame as that produced in the primary pressure-chamber by the movement ofthe thermostatic bar. This pressure may be utilized to operate any formof motor; but I preferably use the one shown in Fig. 4. As hereillustrated, it comprises two parts a and a, which constitute a casingfor a diaphragm g, which is clamped between them. Resting on thisdiaphragm is a piston-plate cl, which actuates alever e, properlysupported from the diaphragm-casing. The piston-plate is firmly pressedagainst the elastic diaphragm by means of suitable springs M M, by whicha variable resistance is secured to the movement of the diaphragm. It isevident that in this form of the appliance the pressure in themotor-chamber will at all times be substantially the same as thatproduced in the primary chamber by the opening and closing of thethermostat-valve.

It is sometimes desirable that the resulting pressure in the secondarymotor should be maintained at'a greater or less tension than that in theprimary chamber. To secure such results, I have provided the means shownin Figs. 2 and 3. This is accomplished in Fig. 2 by the use, inconnectionwith the primary chamber, of a second diaphragm F, difieringin size from that against which the primary airpressure is exerted, asolid piston-plate G being interposed between these two diaphragms, bywhich the movement of one is transmitted to the other. If, as shown inthe drawings, this second diaphragm be made of less area than theprimary one, it follows that more pressure will be required to balancethe pressure primarily produced by the thermostat and to permit thevalve H to reseat,and consequently the resulting pressure in thesecondary chamber or motor will be greater than that existing in theprimary chamber, and-each variation in the primary chamber will resultin an increased ratio in the secondary.

The two diaphragms shown in Fig. 2 may be considered as the equivalentof a single diaphragm or piston having a larger exposed surface on oneside than on the other, this form of the apparatus and that shown inFig. 3 constituting a power-multiplying device.

In Fig. 2 I have omitted the permanent waste '8 and substituted thereforan automatic waste consisting of an opening N through the diaphragm,which, together with the end of the valve H, forms an exhaust- Valve,through which the excess of the airpressure in the motor escapeswhenever a reverse movement of the two diaphragms takes place. With thisconstruction waste of air is prevented, for the reason that the supplyand exhaust valve can never both be open at the same time. When thediaphragms has closed the escape-opening N, and whenever through alowering of the pressure in the primary chamber the diaphragms recedemore than is suflicient to allow valve H to close the opening through Nbecomes ett'ect ive and the air-pressure is discharged until thepressure in the two chambers is brought into proper proportion, due tothe relative size of the two diaphragms. In other respects the operationis the same as in Fig. 1. It is evident that some form of automaticwaste may be used in Fig. 1, if desired.

In Fig. 3 I have shown a diaphragm in a separate chamber 0, to which themotion is transmitted by means of a lever P, this lever being theequivalent of the solid piston G in Fig. 2. This lever rests upon asupport S, which is provided with a series of perforations .9, throughany one of which the pin 3 is adapted to be placed. The lever is alsoprovided with a series of holes which register with those in the frame,so that the pin 3 may be placed in any one of the holes. Thisconstitutes amovable fulcrum, which affords an opportunity to vary therelative pressure in the motor-chamber by changing the leverage. \Viththis construction the diaphragms may each be of the same size and theefiective pressure in the secondary motor may be varied. It is obviousthat in either of these constructions less pressure can be maintained inthe secondary chamber than in the primary by making, in Fig. 2, thesecond diaphragm larger than the first and, in Fig. 3, by moving thefulcrum of the lever to a point nearer the end operated upon by theprimary pressure. In this construction the automatic waste-port. N isemployed.

In Fig. 5 I have shown a heating-coil A arranged in connection with adivided airassa 'e and means for forcim air through the same, (shown atB,) with dampers B B arranged in the two passages to control therelative amounts of the heated and cool air. These dampers are commonlyarranged so that one shall open as the other closes, and vice versa. Thetwo currents of airare mixed in the duct beyond the dampers anddischarged into the apartment through the duct shown. The thermostat,somewhat enlarged, is shown attached to the wall of the apartment and apipe connecting it with the airpressure tanltQ. There is also a pipeleading from the thermostat to the damper-operating motor R. (Shown indetail in Fig. 4.)

It is not the intention to limit my invention to the precise detailsshown, as any form of dampers or valves maybe used to control theair-supply to the apartment; nor is it the intention to limit myself tothe specific form of thermostat shown in the drawings, as any of thewell-known forms of thermostats may be used to open and close the escapefrom the primary chamber.

Fig. 6 shows a modified form of primary chamber where the inlet iscontrolled by the thermostat, the pressure fluid being dischargedthrough a restricted opening 0, constituting a permanent waste. In thisform of the apparatus I use a valve L, which when pressed down by thespring 0 closes the port P and prevents the passage of the pressurefluid into the primary chamber. A is the thermostatic bar, which at itslower end is provided with a cylindrical extension N. The chamber forthe valve L is also provided with a cylindrical extension S. A flexibletube M, usually of rubber, forms an air-tight connection between S andN, which permits of the movement of the valve-actuating rod N, which isconnected with N and which by its outward movement serves to raise thevalve L from its seat. The escape-opening c is provided with arestricting-valve c.

The general theory of my invention and its principle of action are asfollows: The pressure fluid passing from a source of supply is utilizedin a motor for the purpose of regulating temperatures, said motorcontrolling the main valve or damper, and the pressure fluid is admittedto and released from said main-valve motor under the direction andcontrol of a thermostat. This direction and control is secured byinterposing a valve mechanism in the pressure-tlnid-supply pipe, whichvalve mechanism is controlled by a secondary motor, said secondarymot-or having a movable diaphragm or wall, the movement of whichoperates the supply-valve and two connections with a pressure-fluidsupply, these connections being so arranged as to admit thefluid-pressure to opposite sides of the movable part of the supply-valvemotor, the pressures thus admitted acting in opposition to each otherupon the movable part of the supply-valve motor, and one of theconnections being controlled by the thermostat.

Having thus described my invention, what I claim is 1. In aheat-controlling device the combination of a source of fluid-pressuresupply with a chamber having a movable wall and an inlet-port and anoutlet-port, a thermostatically-actuated valve for one of said ports, asecond chamber having an inlet and an outlet port, a valve for theinlet-port, a principal valve, a motor for said valve communieating withthe outlet port of the second chamber, the inlet-valve of said secondchamher being so connected with the movable wall of the first-namedchamber as to be' moved thereby, and the two chambers being so relatedthat the pressure in the second chamber will act in opposition to thepressure in the first-named chamber.

2. In a heat-controlling device, the combination with an expansiblechamber, having an inlet and an outlet for fluid-pressure, one of whichis thermostatically controlled; of a pressure-chamber having a fluid-pressure supply; a valve controlling said supply, said valve beingadapted to be opened by the mov- ITO IIS

able wall of the expansible chamber, whereby to admit the pressure fluidto act on said movable wall in opposition to the pressurethermostatically produced in the expansible chamber.

3. In a heat-controlling device, the combination of a source offluid-pressure, a chamber having an inlet-port and an outlet-portcommunicating with the source of fluid-pressure, athermostatically-actuated valve for one of said ports, a second chamberhaving an inlet-port and an outlet-port, a source of fluid-pressuretherefor, a valve for the inletport, a movable Wall forming one side ofeach chamber, a principal valve, a motor for said valve communicatingwith the outlet-port of the second chamber, the inlet-valve of thesecond chamber being actuated by the movable wall, and the pressures inthe-two chambers acting in opposition to each other, substantially asdescribed.

4. In a heat-controlling device, the combination of a source offluid-pressure, a chamber having an inlet-port and an outlet-portcommunicating therewith,a thermostaticallyactuated valve for one of saidports, a second chamber having an inlet-port and an outletport, a-valvefor the inlet-port, a source of fluid-pressure for the second chamber, amovable wall forming one side of each chamber, the sides of the wallwhich are exposed to pressure being of unequal areas, a principal valve,a motor therefor communicating with the outlet-port of the secondchamber, the inlet-valve of the second chamber being actuated by themovable Wall, and the pressures in the two chambers acting in oppositionto each other, substantially as described.

5. In a heat-controlling device, the combination of a source offluid-pressure, a chamber having an inlet-port and an outlet-portcommunicating therewith,a thermostaticallyactuated valve for one of saidports, a second chamber having an inlet-port and an outletport, a sourceof fluid-pressure for said second chamber, a valve for the inlet-port, aflexible diaphragm forming one side of each chamber, a principal valve,a motor for said valve communicating with the outlet-port of the secondchamber, a Waste-port in the second chamber, the inlet-valve for thesecond chamber adapted to be actuated by the movable Wall, and thepressures in the two chambers acting in opposition to each other,substantially as described.

6. In heat-regulating apparatus, the combination with a fluid-pressuresupply, a heatcontrolling valve 'or damper and a fluid-pressure motorfor operating the same, of valve mechanism for controlling the supplyand release of the fluid -pressure medium to and from said motor, asecondary fluid-pressure motor for operating said valve mechanism, twofluid-pressure supply connections arranged to admit the fluid-pressureto opposite sides of the movable part of said motor, whereby to act inopposite directions upon said movable part, one of said connectionsbeing controlled by said valve mechanism, and a thermostat controllingthe relative supply and waste of the pressure fluid admitted through theother connection, the source of fluid-pressure supply being independentof the thermostat.

7. In a heatcontrolling device, the combination of a source offluid-pressure, a chamber having an inlet-port and an outlet-portcommunicating with the source of pressure, a thermostatically-actuatedvalve for one of said ports, a second chamber having an inletport and anoutlet-port, a source of fluid-pressure for the second chamber, amovable wall forming one side of each of such chambers having an orificeforming communication between the second chamber and the externalatmosphere, a valve governing the inlet-port of the second chamber, avalve-stem attached to the valve of the second chamber, another valve onthe opposite end of this stem adapted to control the orifice through themovable wall, a principal valve, a motor for said valve communicatingwith the outletport of the second chamber, the inlet-valve for thesecond chamber being actuated by the movable wall, substantially asdescribed.

WILLIAM P. POWERS.

Witnesses:

F. W. POWERS, H. M. POTTER.

